基于小波变换的气化燃烧状态诊断试验研究

Experimental Investigation of the Diagnosis of Gasified Combustion Status of a Wavelet-based Transformation

提出了一种通过压力信号分析气流床气化炉火焰气化燃烧状态的有效方法,该方法运用尺度分解法分析炉膛压力时域信号。研究结果发现:在点火前冷态,没有特征频率存在;在点火和灭火状态下,压力信号有一阶跃变化,信号在0 Hz处有一较大的冲击;火焰剧烈波动时,存在2 Hz左右的特征频率;火焰稳定燃烧时,存在着一个40 Hz左右的特征频率。这个现象表明,压力信号在一定频段内的分布与气化炉内火焰燃烧的状态密切相关,随着火焰燃烧稳定性加强,压力信号向高频方向移动。

An effective method is proposed for analyzing through pressure signals the flame gasified combustion condition of an entrained flow gasifier. Under this method a scalar decomposition approach has been utilized to analyze furnace pressure time-domain signals. A study has revealed that in a cold state prior to ignition there exists no characteristics frequency. Under the condition of ignition and flame-extinction the pressure signals experience a step change with the signals at 0 Hz being subjected to a relatively great shock. In time of flame intensive fluctuations there exists a characteristic frequency of about 2 Hz. With the flame in a stable combustion state there will be a characteristic frequency of about 40 Hz. The above phenomenon indicates that within a certain range of frequencies the pressure signal distribution is closely related to the flame combustion condition in the gasified furnace. With the strengthening of flame combustion stability the pressure signals will shift in the direction of higher frequencies.